Tonnis Grade Research Articles

Comparison Between Static and Dynamic Spica Cast for Closed Reduction Cases of DDH: A Short-Term Follow-Up

Background: developmental dysplasia of the hip (DDH) is a typical childhood disease that, if left untreated, can lead to early-onset osteoarthritis. Closed reduction and spica casting are the first line of treatment for infants aged 6-18 months. Static and dynamic spica casts are the two primary treatment method used in practice, but the evidence is mixed as to which method provides the best outcomes. Methods: This prospective, randomized, controlled trial compared static and dynamic spica casting in 98 DDH patients from Kurdistan, Iraq. Patients were divided into dynamic and static groups. The hip was follow-up ed by using radiographic parameters such as the acetabular index and Tonnis grade. Treatment success was defined as a favorable hip outcome after one year. Results: There was no significant difference in treatment success between the groups, with 68% of patients in both groups achieving normal hip modification. However, the dynamic cast group had significantly better acetabular indices at 3, 6, and 12 months, and all of them were done under general anesthesia (GA), better hygiene, better caring and more comfortable parents with less cost. Conclusions: Static and dynamic spica casting have similar short-term clinical success rates for DDH, but dynamic casting produces better radiographic outcomes, especially in infants younger than 1. Longer-term studies are needed to determine possible radiographic improvement and whether dynamic type translate into better clinical outcomes since its more comfortable for parent, with less cost.

Application of 3D-printed individualized porous tantalum buttress in shelf acetabuloplasty for developmental dysplasia of the hip

Shelf acetabuloplasty is a viable treatment for developmental dysplasia of the hip (DDH), yet autologous bone grafts have faced challenges such as morphological mismatch, imprecise placement, and long-term graft resorption. The rapid advancement of three-dimensional (3D) printing technology in orthopedics has enabled the acquisition of digital image correlation method (DICM) data from patient pelvic to bilateral femoral proximal regions through computed tomography (CT) scans. This data is then utilized by software to create 3D models and design individualized metal implants. Using tantalum-based TA1 type I spherical powder as the raw material, a porous tantalum buttress with a pore size of 600 microns and a porosity of 75% was fabricated employing the selective electron beam melting (SEBM) technology. Our Center has applied this 3D-printed individualized porous tantalum buttress in shelf acetabuloplasty for 21 DDH patients (25 hips), including 6 males and 15 females, with a mean age of (21.38±7.39) years. The follow-up period ranged from 12 to 47 months, averaging (22.64±10.86) months. At the final follow-up, patient-reported outcomes (PROs) were used to assess patient’s subjective feelings. Significant improvements were observed in the Non-Arthritic Hip Score (NAHS), modified Harris Hip Score (mHHS), Hip Outcome Score-Sports Subscale (HOS-SSS), International Hip Outcome Tool-12 (iHOT-12), and Visual Analog Scale (VAS) compared with preoperative levels (P<0.01). Radiographic assessments showed that postoperative lateral center edge (LCE) angle, Tonnis angle, acetabular angle (Sharp’s angle), and femoral head coverage all trended towards normal, with statistically significant differences (P<0.01). There was no implant displacement or bone resorption in any case, and no progression in Tonnis grading for hip osteoarthritis (OA) was noted postoperatively, with an 84% patient satisfaction rate. The early follow-up results of 3D-printed individualized porous tantalum buttress in shelf acetabuloplasty are satisfactory, indicating a reliable application prospect for the treatment of DDH patients.

DOES TOTAL HIP ARTHROPLASTY BENEFIT PATIENTS WITH MINIMAL RADIOLOGICAL OSTEOARTHRITIS?

There is some evidence to suggest that outcomes of THA in patients with minimal radiographic osteoarthritis may not be associated with predictable outcomes. The aim of this study was to:Assess the outcome of patients with hip pain who underwent THA with no or minimal radiographic signs of osteoarthritis,Identify patient comorbidities and multiplanar imaging findings which are predictive of outcome,Compare the outcome in these patients to the expected outcome of THA in hip OA.A retrospective review of 107 hips (102 patients, 90F:12M, median age 40.6, IQR 35.1–45.8 years, range 18–73) were included for analysis. Plain radiographs were evaluated using the Tonnis grading scale of hip OA. Outcome measures were all-cause revision; iHOT12; EQ-5D; Oxford Hip Score; UCLA Activity Scale; and whether THA had resulted in the patient's hip pain and function being Better/Same/Worse.The median Oxford Hip Score was 33.3 (IQR 13.9, range 13–48), and 36/107 (33.6%) hips achieved an OHS≥42. There was no association between primary hip diagnosis and post-operative PROMs. A total of 91 of the 102 patients (89.2%, 93 hips) reported that their hip pain and function was Better than prior to THA and would have the surgery again, 7 patients (6.8%, 10 hips) felt the Same, and 4 patients (3.9%, 4 hips) felt Worse and would not have the surgery again.Younger patients undergoing total hip arthroplasty with no or minimal radiographic osteoarthritis had lower postoperative Oxford Hip Scores than the general population; though most felt symptomatically better and knowing what they know now, would have surgery again. Those with chronic pain syndrome or hypermobility were likely to benefit less. Those with subchondral cysts or joint space narrowing on CT imaging were more likely to achieve higher functional scores and satisfaction.

Poster 218: Localized Acetabular Bone Density Distributions Are Altered in Unilateral Femoral Acetabular Impingement

Objectives: Femoral acetabular impingement (FAI) can lead to bony and cartilage changes at the joint, and it has been suggested that changes in bone mineral density in the acetabulum may correlate with osteoarthritic degeneration of the hip. In this study, we aimed to use opportunistic quantitative computed tomography (QCT) to map density distributions across the acetabular region in patients with unilateral FAI and determine if there were differences between the affected and unaffected side. Furthermore, we assessed if these differences in density distributions were associated with radiographic measures of FAI. Methods: Twenty patients (age 31.9 (SD 9.2), 13 female) who underwent surgery for unilateral FAI and had an associated CT scan of both hips were included in this retrospective study. Both sides of the pelvis were segmented, and 3D models were created. Estimated bone density values were mapped across the bone models via QCT. A thin-spline semi-landmarking approach was used to allow density values at equivalent anatomical points to be compared within patients and across the group. With the contralateral side used as the control, differences in bone density between sides were calculated. A mixed effect linear regression model was used to determine if there were associations between the localized bone density and radiographic measures of Tonnis grade, alpha angle, lateral center edge angle (LCEA), and cross over sign, while controlling for age and sex. To visualize the data, density changes and statistical results were color-mapped to the bone models. Results: Overall, several regions of the acetabulum were found to have increased bone density in the affected side compared to the contralateral (Figure 1). Specifically, the anterior-superior parts of the acetabular rim appeared to be most affected, along with the posterosuperior region (Figure 2). Limited associations were found between localized density and the clinical variables, with the most notable finding being a region of the superior rim that was found to be associated with the alpha angle (Figure 3). Conclusions: FAI leads to distinct patterns of bone density changes around the acetabulum, although there is still variability at the level of the individual patient. It is unclear whether these changes in bone density may be related to the underlying condition, alterations in the patient’s mechanics due to pain, or a combination of these factors. Providing detailed density maps of the bony anatomy may also assist surgical providers in planning interventions. Further research may elucidate the relationship between bone density changes and long-term degeneration of the joint.

Ultrasound-Guided Hip Injections with High Density Hyaluronic Acid: Outcome at One Year Follow Up.

Background: The ultrasound-guided viscosupplementation of the hip joint with hyaluronic acid (HA) is considered a standard procedure among the conservative treatments for hip arthritis. The aim of this study was to evaluate the clinical benefit and the incidence of adverse events of the technique in an observational study at one year follow up. Methods: We evaluated a consecutive series of 85 patients with a diagnosis of symptomatic arthritis who underwent intra-articular ultrasound-guided hyaluronic acid injections. The scales used for evaluation were modified Harris Hip Score (mHHS), WOMAC (Western Ontario and McMaster University), and Hip Outcome Score (HOS) with subscale Sport (HOSs), for pain the Visual Analogic Scale (VAS). The patients were classified according to Tonnis' radiological classification of arthritis (range 0-3): 20 patients (grade 0), 32 (grade 1), 18 (grade 2), 15 (grade 3). Results: At last follow up, all the scales increased: mHHS from 59.35 to 82.1, HOS from 69.45 to 78.53, HOss from 47.4 to 58.11, VAS from 6.09 to 3.97, WOMAC from 33.2 to 31.5 (p < 0.05 for all the parameters); the results were elaborated with GraphPad Prism v5.0 (Prism Software La Jolla, CA, USA) using Wilcoxon's test. A total of 13 patients out of 85 needed arthroplasty, all classified as Tonnis grade 3. No serious adverse events were noted due to the procedure. Conclusions: Based on our findings, indication for the use of hyaluronic acid is limited to patients with mild to moderate arthritis. Patients in advanced arthritis refusing replacement surgery and asking for this treatment should be informed about the poor results of the technique even in the short term.

MACHINE LEARNING CAN PREDICT DIFFICULTY IN ANTERIOR APPROACH TOTAL HIP ARTHROPLASTY TO IMPROVE PATIENT SAFETY AND SURGICAL TRAINING

Anterior approach total hip arthroplasty (AA-THA) has a steep learning curve, with higher complication rates in initial cases. Proper surgical case selection during the learning curve can reduce early risk. This study aims to identify patient and radiographic factors associated with AA-THA difficulty using Machine Learning (ML).Consecutive primary AA-THA patients from two centres, operated by two expert surgeons, were enrolled (excluding patients with prior hip surgery and first 100 cases per surgeon). K- means prototype clustering – an unsupervised ML algorithm – was used with two variables - operative duration and surgical complications within 6 weeks - to cluster operations into difficult or standard groups.Radiographic measurements (neck shaft angle, offset, LCEA, inter-teardrop distance, Tonnis grade) were measured by two independent observers. These factors, alongside patient factors (BMI, age, sex, laterality) were employed in a multivariate logistic regression analysis and used for k-means clustering. Significant continuous variables were investigated for predictive accuracy using Receiver Operator Characteristics (ROC).Out of 328 THAs analyzed, 130 (40%) were classified as difficult and 198 (60%) as standard. Difficult group had a mean operative time of 106mins (range 99–116) with 2 complications, while standard group had a mean operative time of 77mins (range 69–86) with 0 complications. Decreasing inter-teardrop distance (odds ratio [OR] 0.97, 95% confidence interval [CI] 0.95–0.99, p = 0.03) and right-sided operations (OR 1.73, 95% CI 1.10–2.72, p = 0.02) were associated with operative difficulty. However, ROC analysis showed poor predictive accuracy for these factors alone, with area under the curve of 0.56. Inter-observer reliability was reported as excellent (ICC &gt;0.7).Right-sided hips (for right-hand dominant surgeons) and decreasing inter-teardrop distance were associated with case difficulty in AA-THA. These data could guide case selection during the learning phase. A larger dataset with more complications may reveal further factors.

Physical Therapy May Not Be Successful for Patients With Cam-Type Femoroacetabular Impingement Syndrome and May Result in Insufficient Hip Range of Motion When Femoral Anteversion Is Less Than 16° and α-Angle Is Greater Than 65°

To identify factors associated with insufficient range of motion (ROM) improvement after the posterior pelvic tilt change in cam-type femoroacetabular impingement syndrome. Preoperative computed tomography images from 71 consecutive patients with femoroacetabular impingement syndrome treated with arthroscopic cam resection were evaluated. Using a dynamic computer simulation program, 3-dimensional models with a 10° posterior pelvic tilt from the supine functional pelvic plane (baseline) were created by computed tomography models. Patients were divided into 2 groups: those who experienced >10° (effective group) and ≤10° (ineffective group) improvements in internal rotation at 90° flexion after a 10° posterior pelvic tilt. Demographic characteristics; preoperative range of internal rotation at 90° flexion; and radiographic parameters, including Tönnis grade, lateral center-edge angle, acetabular roof obliquity angle, central acetabular anteversion, cranial acetabular anteversion, femoral anteversion, and α angle, were compared in the 2 groups. Univariate and multivariable logistic regression analyses were performed to evaluate factors associated with insufficient ROM improvement following a 10° posterior pelvic tilt. The 71 patients included 58 men and 13 women, of mean age 41.4 ± 14.6 years. Posterior pelvic tilt was effective in 13 hips and ineffective in 58. Univariate analysis showed that preoperative range of internal rotation at 90°flexion, femoral anteversion, and α angle differed significantly in the 2 groups. Multivariable analysis showed that femoral anteversion <16° (odds ratio 7.4; 95% confidence interval 1.6-35; P= .012) and α angle >65° (odds ratio 6.7; 95% confidence interval 1.2-37; P= .027) were significant factors associated with insufficient ROM improvement after posterior pelvic tilt. Physical therapy may not be successful for patients with cam-type femoroacetabular impingement syndrome and may result in insufficient hip ROM when femoral anteversion is less than 16° and α-angle is greater than 65°. Patients with a prominent cam-type deformity and lower anterior femoral anteversion are at high risk of clinical failure following improvement in pelvic mobility by conservative treatment alone and are likely to benefit from surgery for cam deformity.

Improved Functional Outcomes of Combined Hip Arthroscopy and Periacetabular Osteotomy at Minimum 2-Year Follow-Up

To evaluate patient-reported outcomes (PROs) and survivorship at minimum 2-year follow-up after combined hip arthroscopy and periacetabular osteotomy (PAO) performed in the setting of a single anesthetic event. Patients who underwent combined hip arthroscopy (M.J.P.) and PAO (J.M.M.) between January 2017 and June 2020 were identified. Preoperative and minimum 2-year postoperative PROs including Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sport, modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Osteoarthritis Index, 12-Item Short Form Survey Mental Component Scores (SF-12 MCS), and 12-Item Short Form Survey Physical Component Score were collected and compared in addition to revision rate, conversion to total hip arthroplasty (THA), and patient satisfaction. Twenty-four of 29 patients (83%) eligible for the study were available for 2-year minimum follow-up with a median follow-up time of 2.5 years (range, 2.0-5.0). There were 19 females and 5 males with mean age of 31 ± 12 years. Mean preoperative lateral center edge angle was 20° ± 5° and alpha angle was 71° ± 11°. One patient underwent reoperation for removal of a symptomatic iliac crest screw at 11.7 months after operation. Two patients, a 33-year-old woman and a 37-year-old man, were converted to THA at 2.6 and 1.3 years, respectively, following the combined procedure. Both patients had a Tönnis grade of 1 on radiographs, as well as bipolar Outerbridge grade III/IV defects requiring microfracture of the acetabulum. For patients who did not convert to THA (n= 22), there was significant improvement from before to after surgery for all scores (P<.05) except SF-12 MCS. The minimal clinically significant difference and patient-acceptable symptom state rates for HOS-ADL, HOS-Sport, and mHHS were 72%, 82%, 86%, and 95%, 91%, and 95%, respectively. Median patient satisfaction was 10 (range, 4 to 10). Single-stage combined hip arthroscopy with periacetabular osteotomy for patients with symptomatic hip dysplasia results in improvement in PROs and arthroplasty free survivorship of 92% at median 2.5 year follow-up. Level IV, case series.

The Relationship Between the Joint Space and Outcomes After Hip Arthroscopic Surgery for Femoroacetabular Impingement: Reevaluating the 2-mm Rule

Background: A limited joint space (<2 mm) is associated with poorer outcomes and conversion to total hip arthroplasty (THA) after hip arthroscopic surgery. As indications for hip arthroscopic surgery expand, it is important to reevaluate established risk factors among large patient populations. Purpose: To reevaluate the relationship between the radiographic joint space and outcomes after hip arthroscopic surgery and to assess the validity of a joint space of 2 mm as the accepted cutoff for successful hip arthroscopic surgery. Study Design: Cohort study; Level of evidence, 3. Methods: Patients aged 18 to 50 years who underwent hip arthroscopic surgery for femoroacetabular impingement between January 2008 and December 2016 and had a minimum 2-year follow-up were included. Patients with previous ipsilateral hip surgery, a history of hip fractures, dysplasia (lateral center-edge angle <20°), or osteoarthritis (Tonnis grade >2) were excluded. The joint space was categorized as diminished (≤2 mm), borderline (>2 to ≤3 mm), or preserved (>3 mm). Minimum 2-year patient-reported outcomes (modified Harris Hip Score [mHHS], Hip Outcome Score–Activities of Daily Living [HOS-ADL], Hip Outcome Score–Sports-Specific Subscale [HOS-SSS]), revision rates, and rates of conversion to THA were compared between groups. Results: A total of 699 patients (782 hips) with a mean age of 33.8 ± 10.1 years met 2-year inclusion criteria. The mean follow-up time was 4.2 ± 2.1 years. Overall, 51 hips (6.5%) had a diminished joint space, 297 (38.0%) had a borderline joint space, and 434 (55.5%) had a preserved joint space. Patients with a diminished joint space had larger femoral and acetabular defects compared with those with larger joint spaces. All groups had improved patient-reported outcome scores compared with baseline (P < .001 for all), and there were no differences between the groups in the percentage of patients who reached the minimal clinically important difference or patient acceptable symptom state. There were also no differences between the groups in revision rates (P = .95). A greater number of hips with a diminished joint space converted to THA (n = 8 [15.7%]) compared with those with a borderline (n = 9 [3.0%]) or preserved (n = 9 [2.1%]) joint space (P < .001). Considering joint space as a continuous variable, adjusted logistic regression showed that for every millimeter decrease in the joint space, the odds of conversion to THA increased by a factor of 2.5 (odds ratio, 2.5 [95% CI, 1.6-3.8]). Conclusion: This study demonstrated that patients with a diminished joint space were at a higher risk of conversion to THA. Although 2 mm should not serve as a strict cutoff, patients should be counseled based on their preoperative radiographic findings accordingly.

Risk factors for postoperative avascular necrosis of the femoral head in children with developmental dysplasia of the hip.

To investigate factors associated with postoperative avascular necrosis of the femoral head (ANFH) in developmental dysplasia of the hip (DDH) patients, and if or how the associations varied among different subpopulations of age, sex and surgical method. Patients with DDH were enrolled between October 31, 2016 and July 15, 2020 in this retrospective cohort study. The average follow-up time was 21.42 ± 10.02 months. The outcome was postoperative ANFH. The main study variables were the DDH classification, Tonnis grade, International Hip Dysplasia Institute (IHDI) classification, and preoperative traction. Multivariate logistic regression was employed to assess the associations between main study variables and postoperative ANFH. Subgroup analysis was carried out based on age at reduction, sex and surgical method. Odds ratio (ORs) and 95% confidence intervals (CIs) were calculated. A total of 427 children with DDH were included, with 92 (21.55%) in the ANFH group, and 335 (78.45%) in the non-ANFH group. DDH classification was positively correlated with the risk of postoperative ANFH (OR = 4.14, 95% CI, 1.08-15.77, P = 0.038). Children with preoperative traction had a significantly decreased risk of postoperative ANFH in contrast to those without preoperative traction (OR = 0.37, 95% CI, 0.22-0.61, P < 0.001). Children aged 1-3 years who received preoperative traction has a significantly reduced risk of postoperative ANFH than those who did not receive preoperative traction (OR = 0.28, 95% CI, 0.15-0.51, P < 0.001). For children aged >3 years, positive association was found between DDH classification and the risk of postoperative ANFH (OR = 3.75, 95% CI, 1.51-9.31, P = 0.004). Girls with a more severe DDH type had a significantly higher risk of postoperative ANFH (OR = 3.80, 95% CI, 1.80-8.02, P < 0.001). Receiving preoperative traction was associated with a significantly decreased risk of postoperative ANFH in girls (OR = 0.37, 95% CI, 0.22-0.61, P < 0.001). For children undergoing open reduction, DDH classification was positively associated with the risk of postoperative ANFH (OR = 3.01, 95% CI, 1.65-5.50, P < 0.001), and those with preoperative traction had a lower risk of postoperative ANFH compared with those without preoperative traction (OR = 0.35, 95% CI, 0.20-0.61, P < 0.001). DDH classification and preoperative traction were associated with the risk of postoperative ANFH, and these associations varied across DDH patients with different ages, sexes and surgical methods.

Revealing the Effect of Spinopelvic Alignment on Hip Disorders.

Hip osteoarthritis (HOA) is a growing burden and one of the leading causes of hip pain. The relationship between the HOA and the alignment of the spinopelvic region has been intensively studied, however the issue remains controversial. Spinopelvic imbalance, HOA, and dysplasia were investigated in relation to sagittal spinopelvic parameters in this study. We collected computerized tomography (CT) topograms of the pelvis or abdomen from 380 patients. In antero-posterior (AP) topograms, Tonnis grading, center-edge angle (CEA) and Sharp's acetabular angle (AA) measurements were performed on each patient. Lateral topograms were used to evaluate the following spinopelvic parameters for each patient: pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), sacral table angle (STA), lumbar lordosis (LL), proximal lumbar lordosis (PLL), distal lumbar lordosis (DLL), and PI-LL difference. Initially, the cohort was divided into two subgroups based on whether or not they had HOA. Then, they were divided into two subgroups based on whether or not they had dysplasia. Ultimately, it was divided in half based on the PI-LL imbalance. Statistical analyses were conducted to determine the likely correlations between the spinopelvic parameters of these subgroups. In addition, the correlations between spinopelvic parameters were investigated. There were 380 patients evaluated. We found no association between HOA or dysplasia and spinopelvic parameters. In addition, there was no association between PI-LL imbalance and HOA or dysplasia. There was no difference in constant PI and STA angle, besides other variable parameters, between groups having HOA and dysplasia or not. PI-LL imbalance has no effect on HOA and dysplasia.

Paper 57: Labral Tear Management in Patients Aged 40 Years and Older Undergoing Primary Hip Arthroscopy: A Propensity-Matched Case-Control Study Comparing Labral Reconstruction to Labral Repair with Minimum Two-Year Follow-Up. *ACCEPTED TO AJSM*

Objectives:To report minimum two-year patient-reported outcome (PRO) scores, survivorship, and secondary surgeries, in patients aged ≥ 40 years who underwent primary hip arthroscopy with labral reconstruction compared to a propensity-matched primary labral repair group.Methods:Data were prospectively collected and retrospectively reviewed for patients who underwent a primary hip arthroscopy for femoroacetabular impingement syndrome from January 2014 to June 2018. Patients aged ≥ 40 years who underwent a labral reconstruction or a labral repair and had preoperative and minimum two-year PROs for the modified Harris Hip Score (mHHS), Non-arthritic Hip Score (NAHS), and visual analog scale (VAS) for pain were included. Patients with prior ipsilateral hip conditions and surgery, Tonnis grade > 1, hip dysplasia, or worker’s compensation status were excluded. Patients in the reconstruction group were propensity-matched 1:2 to patients in the repair group based on age, sex, and body mass index. Secondary surgeries and the achievement of the minimal clinically importance difference (MCID), patient acceptable symptomatic state (PASS), and maximum outcome improvement (MOI) were recorded.Results:Fifty-three and 106 hips were included in the labral reconstruction and repair groups, respectively. The average follow-up time was 37.6 months. The average age for the reconstruction and repair groups were 48.01 ± 5.4 years and 48.61 ± 6.0 years, respectively. Both groups achieved significant improvements in all PROs at minimum two-years with similar achievements of MCID, PASS, and MOI. Both groups showed comparable secondary surgeries rates.Conclusions:Patients aged 40 years and older who received primary labral repair and primary labral reconstruction, achieved similar significant improvements in all PROs, VAS pain, and patient satisfaction at minimum two-year follow-up, with comparable rates of secondary surgeries and achieving MCID, PASS, and MOI. Based on these findings, labral repair remains the gold standard treatment for viable labrum in this population group, while reconstruction is a useful alternative for irreparable labrum.

Acetabular Cartilage Lesions Predict Inferior Mid-Term Outcomes for Arthroscopic Labral Repair and Treatment of Femoroacetabular Impingement Syndrome

To analyze the effect of acetabular chondrosis at a minimum of 2 years following hip arthroscopy in patients undergoing labral repair and treatment of femoroacetabular impingement. From 2014 to 2017, patients undergoing arthroscopic labral repair were prospectively enrolled in a multicenter hip arthroscopy registry. The registry was retrospectively queried for primary labral repair patients with complete 2-year outcomes and a Tonnis grade of less than 2. Patients were grouped according to severity of articular cartilage damage noted intraoperatively using the Beck classification system: none, low-grade (Grade 1 or 2), or high-grade (Grade 3 or 4) damage. A Kruskal-Wallis test and post hoc Dunn's test with Holm correction compared 2-year postoperative outcome scores of the iHOT-12 scale between groups. The proportion of patients in each cohort who achieved the clinically significant thresholds of the minimum clinically important difference (MCID), patient-acceptable symptom scale, and substantial clinical benefit (SCB) were analyzed. Multivariate logistic regression models identified predictors of achieving clinical thresholds while controlling for demographic variation. 422 patients met inclusion criteria, from which 347 completed 2-year outcomes. All groups experienced improvement in iHOT-12 scores from baseline to follow-up (P < .001). iHOT-12 scores at follow-up were inferior for Low-Grade Damage and High-Grade Damage Groups relative to the No Damage Group (P= .04; P= .03). When accounting for age, body mass index, gender, and preoperative iHOT-12 scores in logistic regression models, the presence of high-grade lesions was a negative predictor for achieving SCB (OR [95% CI], 0.54 [0.29-0.96]) and low-grade lesions a negative predictor for achieving MCID (0.50 [0.27-0.92]. Among patients with high-grade lesions, there was no significant difference in 2-year iHOT-12 scores between those undergoing chondroplasty (n= 50) and those undergoing microfracture (n= 14) (P= .14). Acetabular cartilage damage portends inferior patient-reported outcomes 2 years after primary labral repair and treatment of femoroacetabular impingement. The presence of cartilage lesions was a negative predictor of individual achievement of several clinical thresholds. III, Retrospective comparative cohort.

Salter pelvic osteotomy for the treatment of Developmental Dysplasia of the Hip: assessment of postoperative results and risk factors.

If non-surgical treatment of Developmental Dysplasia of the Hip (DDH) fails or if DDH is late-detected, surgery is necessary. Salter pelvic osteotomy (SPO) is an effective surgical option for such cases. To study the results after SPO; to evaluate risk factors; to reveal radiological parameters that may correlate with results. Results analysis in 17 patients (22 hips). Risk factors included those that do not depend on the surgeon (patient's age, value of the acetabular index (AI) preoperatively, DDH Tonnis grade) and those that depend on the surgeon (amount of AI correction). To radiological parameters which may correlate with the amount of AI correction we referred distance "d" and the lateral rotation angle. SPO allows performing AI correction in ranges 24.1 ± 6.5°. Excellent and good clinical results were obtained in 95.5% of patients; excellent and good radiological results in 86.4% of patients. Risk factors that do not depend on the surgeon were older patient's age and higher preoperative AI values (p <0.05). The risk factor that depends on the surgeon was the amount of AI correction (p <0.05). The distance "d" was recognized as a radiological parameter that may indicate sufficient AI correction (p <0.05). In older patients with a higher preoperative AI value the results will be predictably worse. The surgeon may influence the result with a greater amount of AI correction (which may also be indicated radiologically by the distance "d" values). IV, therapeutic, case series.

Radiological Evaluation of the Hip of Patients with Congenital Zika Syndrome

Introduction: Congenital Zika syndrome can generate microcephaly and spastic motor syndromes, limb deformities, and arthrogryposis. Hip dysplasia, associated with this syndrome, is frequent but poorly studied. Objective: To describe the radiographic alterations of the hip in patients with Congenital Zika Syndrome (CZS). Methods: Observational cross-sectional cohort study. We studied 25 patients with a serological diagnosis of CZS and a sample of 50 hips. Patients underwent evaluation, with lines and angles drawn on AP and P radiographs of the pelvis to assess the relationship between the femoral head and the acetabulum. The correlation was performed between radiographic changes of the hip in patients with SZC, gender, presence of arthrogryposis, spasticity, and microcephaly. Results: The mean age was 36 months (29-45 months), 15 patients were female (60%), with a predominance of blacks and browns (72%). The mean maternal age was 28 years (16-44 years), 11 (44%) had the disease before the 12th week of gestation, and all had clinical symptoms related to ZIKA virus infection. At birth, patients had an average head circumference of 26 cm (26-32 cm). Of the 50 hips evaluated in the study, 38 (76%) hips patients had orthopedic deformities, and 20 (40%) hips patients had arthrogryposis. In the radiographic changes of the hip, of the 50 hips, 12 (24%) hips were Tonnis grade I, 22 (44%) were subluxated (grade II), 9 (18%) were low dislocated (grade III), and 7 (14%) were high dislocated (grade IV). The RI was changed in 43 (86%) hips. ACD was valgus in 45 (90%) hips. ACEW was changed in 13 (26%) hips. The IA was changed in 18 (36%) of the evaluated hips. Conclusion: We found a high frequency of dysplastic changes in the hip in the patients of this study. So, we indicate radiological investigation of the hip in children with microcephaly and suspected CZS.

Collagen I in the Hip Capsule Plays a Role in Postoperative Clinical Function in Patients With Developmental Dysplasia of the Hip.

The aims of the present study is to evaluate the roles of collagen I and III in the hip capsule in the postoperative clinical function of patients with developmental dysplasia of the hip (DDH). Hip capsules from 155 hips of 120 patients were collected during surgery. The patients were divided into three groups according to age: I: 2–3.5 years; II: 3.5–5 years; and III: 5–6 years. Patient clinical function and radiographic outcomes were evaluated with the McKay scores and Severin classification. The expression of collagen I and III was detected through immunohistochemistry and quantitative reverse transcription polymerase chain reaction (RT-PCR) and analyzed according to age, sex, degree of dislocation and McKay classification. All patients received open reduction and pelvic osteotomy and/or femoral shortening osteotomy and achieved good results on the basis of postoperative X-ray imaging. The average follow-up time was 3.4 years (range 2–4.3 years). There were no changes in the expression of collagen III in the different groups. The expression of collagen I according to age and sex was not significantly different. Lower expression of collagen I was observed in DDH patients with a higher degree of dislocation according to the Tonnis grade. The highest expression of collagen I was detected in the group with poor clinical function according to the McKay classification. Collagen I is correlated with the degree of dislocation and is a risk factor for poor clinical function in DDH patients. Collagen I is correlated with the degree of hip dislocation and poor clinical function in DDH patients.

Younger Age, Capsular Repair, and Larger Preoperative Alpha Angles Are Associated With Earlier Achievement of Clinically Meaningful Improvement After Hip Arthroscopy for Femoroacetabular Impingement Syndrome

The purpose of the study was to analyze demographic, radiographic, and intraoperative factors that influence the time to achieve the minimal clinically important difference (MCID) and maximum outcome improvement satisfaction threshold (MOIT) after primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS) and labral tear. Included patients had undergone hip arthroscopy with labral repair or reconstruction for FAIS with labral tear between February 2008 and October 2018. Patients were excluded if they had a prior ipsilateral hip surgery, prior hip conditions, a Tonnis grade > 1, or were unwilling to participate. Multiple demographic, radiographic, and intraoperative variables were collected. The modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS) were collected before surgery and at 3 months, 1 year, and 2 years after surgery. The MCID and MOIT for the mHHS and NAHS were either calculated or determined through previously published values. A time-to-event analysis was performed to determine variables predictive of early or delayed achievement of MCID or MOIT. Early achievement was defined as achieving MCID or MOIT at the 3-month timepoint. Six hundred thirty-two hips (632 patients) were included. Of those that achieved MCID and MOIT, 428 (73.0%) and 414 (73.0%) patients achieved MCID and 253 (47.9%) and 264 (52.5%) patients achieved MOIT by 3 months after surgery for mHHS and NAHS, respectively. Younger age, capsular repair, and increasing alpha angle were associated with earlier achievement for either MCID or MOIT. Increasing age, worker's compensation claims, and higher baseline patient-reported outcome measure scores were associated with delayed achievement for either MCID or MOIT. Most of the patients who achieved MCID and MOIT for mHHS and NAHS did so by 3 months after surgery. Younger age, capsular repair, and increasing alpha angle were associated with earlier achievement of MCID and MOIT after hip arthroscopy. Level IV, case series.

Efficacy of tantalum rod insertion for preventing femoral head collapse in osteonecrosis in a paediatric population: a pilot study.

ABSTRACTFemoral head osteonecrosis in the paediatric population is difficult to treat, with the primary goals of management being prevention of subchondral collapse and the avoidance of early total hip replacement. This study aims to describe the use of a porous tantalum rod implant to provide mechanical support in preventing femoral head collapse in a paediatric population. A retrospective chart-based analysis of patients with osteonecrosis of the hip was performed at our institution to identify those who had undergone tantalum rod insertion. A total of 10 patients (fives males and five females, median age 12.5 years, 9–18) had tantalum rods implanted between December 2013 and February 2018. One patient was excluded due to follow-up at a different institution. The radiographic degree of osteonecrosis was characterized according to the Ficat classification and the Kerboul angle. Radiographic assessment of pre- and post-operative plain films was performed. The outcome measures were Tonnis grade and percentage collapse of the femoral head. Nine patients with a mean follow-up time of 18.4 months were included in the analysis. There was no significant increase in the femoral head collapse percentage post tantalum rod insertion compared to pre-operatively (P = 0.63). There was a significant increase in the Tonnis grade post-operatively (P < 0.05), with sub-group analysis showing minimal increase in Ficat Stage 1 patients. This study is the first to examine the role of tantalum rod insertion in preventing femoral head collapse in a paediatric population, with results suggesting potential benefit in a subset of patients.

Core Decompression and Bone Marrow Aspirate Concentrate in the Treatment of Femoral Head Avascular Necrosis in Pediatric Sickle Cell Disease: Can We Improve Natural History?

Femoral head avascular necrosis (AVN) affects between 10% and 41% of children with sickle cell disease (SCD), resulting in the development of proximal femoral deformity and residual hip pain in the majority of patients without treatment. There have been multiple adult studies published on the outcomes of core decompression with and without the use of bone marrow aspirate concentrate (BMAC) injection both in idiopathic and SCD-related AVN with promising results, however, few studies have reported on outcomes in skeletally immature patients. This study sought to report on a single surgeon's outcomes for core decompression with BMAC injection in pediatric patients with AVN of the femoral head secondary to underlying SCD. A single-center, retrospective review was performed for pediatric patients undergoing core decompression with BMAC injection for femoral head AVN in patients with SCD with a minimum of 12-month follow-up. Demographic, radiographic, and clinical variable were collected. Patients were subdivided based upon presence of open femoral physes at the time of surgery. Successful treatment was defined as the ability to return to activities without limitations. A total of 13 patients (average age 14.1±2.8 y, 84.6% male, 6 skeletally immature and 7 skeletally mature) with 18 affected extremities were identified. Open physes were present in 50% of operative extremities. Skeletally immature patient demonstrated reconstitution of the femoral head in 78% of cases and 89% demonstrated regression of at least 1 Steinberg grade and none had progression. Skeletally immature patients were significantly more likely to return to activities (100% vs. 55.6%, P=0.023) and achieve a final Tonnis grade <2 (89% vs. 44%, P=0.046). Core decompression appears to alter the natural history of AVN in skeletally immature patients with SCD. Skeletal immaturity was a positive prognostic factor for the ability to return to activities without pain and achieve a lower Tonnis grade at final follow-up.

Analysis of Factors Affecting Early Functional Recovery of Bernese Periacetabular Osteotomy.

ObjectivesTo explore factors affecting the efficacy of Bernese periacetabular osteotomy for the treatment of hip dysplasia.MethodsA retrospective study was conducted on 44 patients with hip dysplasia who underwent Bernese periacetabular osteotomy with a modified Smith‐Peterson approach between January 2017 and November 2019. Among them, 40 were women and four were men. The average age was 31.2 ± 9.4. Preoperative and postoperative imaging parameters were measured. The acetabular top tilt angle, lateral central edge angle, acetabular abduction angle, femoral head extrusion index, sphericity index of femoral head, Shenton line, Tonnis grade of osteoarthritis, joint congruency, p/a ratio, acetabular anteversion angle, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale scores, and modified Harris hip score (MHHS) were observed. MHHS were divided into three clinically relevant categories: poor (<70 points), good (70–85 points), and excellent (86–91 points). Patient demographic data, as well as preoperative and postoperative radiographic parameters, were subjected to univariate logistic regression analysis. Multiple regression analysis was used to determine factors influencing postoperative MHHS.ResultsThe follow‐up time was 1.0–3.9 years after surgery, with an average of 1.6 years. By the last follow‐up, MHHS increased from 70 points before surgery to 91 points after surgery (P < 0.001), WOMAC pain score decreased from 4 points before surgery to 0 points after surgery (P < 0.001). WOMAC functional score decreased (Preoperative: 18.0 [4.0]; Postoperative: 4.0 [0], P = 0.004). Six patients had sensory disturbance of the lateral femoral cutaneous nerve, four of which recovered completely during follow‐up. No other complications related to surgical approach, osteotomy, acetabular displacement, acetabular fixation, and postoperative stage were found. There was no significant vascular, nerve, or visceral injuries in any of the patients. On multiple regression analysis, the probability of the postoperative modified Harris hip score of a hip joint with a preoperative lateral center edge angle ≥4.5° being classified as excellent was six times that of angles <4.5° (Exp[β]: 6.249, 95% CI: 1.03–37.85, P = 0.046). Regression analysis of other factors found no significant correlation with postoperative functional scores.ConclusionOverall functional scores post‐PAO significantly improved, and pain symptoms were significantly reduced. Patients with a preoperative lateral center edge angle ≥4.5° had better joint function after surgery.